Why can't Xiaomi's mobile phone notification ringtone be changed

After restarting, click Enter Settings, select All Settings, and then select Sound and Vibration Settings Notification Ringtone.

Specific operation method:

1. After restarting the phone, click Enter Settings.

2. After entering, select all settings and click Enter.

3. After entering, select Sound and Vibration, and click Enter.

4. After entering, select the notification bell and set it.